Hey guys - I have a female character in mind. I need a male or female dom. Your character would be a doctor in a sci-fi world. He or she doesn't have the best reputation, as you prefer to experiment rather than heal My character however has no other choice. She is an alien of this race:

(Both females and males have a dark, midnight-blue hue to their skin, that often appears iridescent. They appear to be human in form otherwise, except for fully poseable, prehensile tails. Females have two vaginas; the first is a little higher up than a human one would be, and is greatly pleasurable for males. However, it is not so much so for females, and it does not have the capability to produce offspring. The second is lower behind/between the legs, and is greatly pleasurable for the female but takes a great deal of effort for the male. Since the males of the race are decidedly selfish females are usually sexually frustrated. Sometimes particularly loving males will provide a dildo for the second hole during sex, or the female will use her tail to make it more fun for herself.

The race is dying due to the fact that not many males want to interact with the second hole (the one that produces offspring). Additionally, it is difficult for this race to find medical care and other essentials because they are normally shunned from 'respectable' society, due to the fact that their mating practices and other sexual practices usually occur in public without care for who is watching. )

Hopefully you would make my character believe certain things are routine tests, and then once my character figures out your motives are not altruistic, you can get into any sort of crazy experiment you want.